Hydraulic hoist



Mardi-4, 1941- l E. R. BARRETT 2,234,134

amnwmc nozs'r Filed D'ec. 8, 1939 2 Sheets-Sheet 1 qP/sI/cl.. TTORNEYS.-

NVENTOR 5a/722%@ Matth 4, 1941. E, R, BARRETT mnmwmc mais? Filed Das. e, 1939 2 Sheets-Sheet V INVENTOR Zin/.41:47 7i Barn-fifi: BY

9 ATTORNEE.

l Patented Mar. 4, 1941 UNITED STATES PATENT OFFICE Ind.,

ration of michigan Detroit, Mich., o corpo- Appiieaiien neeember s, 1939, serial No. scatti illalms.

The present invention relates to motor vehicles and particularly relates to hoisting mechanism for tilting a tiltable truck body about the oh of a truck. Hoisting mechanisms of the type to which the present invention is directed include an hydraulic cylinder, which is pivotally connected to the chassis of the truck, having a reciprocating piston associated therewith which is m connected to the truck body.

One of the primary objects of the present invention is to provide improved hydraulic hoisting mechanisms of the type mentioned wherein an .hydraulic hoisting cylinder is pivotally connected 35 to the truck chassis andis constructed in such a way that the forces lof the body load exerted on the pivotal connection through the cylinder are translated thereto through a rugged and simple construction in an improved manner.

Another object of the invention is the provision of an improved hydraulic hoisting mechanism including fluid reservoir means'of a novel and simple construction and arrangement.

Another object of the invention is to piovide ---improved hydraulic hoisting mechanism whereby the weight of the structure is considerably .reduced and whereby the structure is simpler and more economical to produce than prior constructions.

Another object of the invention is to provide improved hydraulic hoisting mechanisms of the type mentioned, being so constructed that pump means may be mounted on either side of the `cylinder so that such mechanism may be used 'with diierent makes of trucks without alteration thereto.

Other objects of the invention will become apparent from the following speciiication, the drawings relating thereto, and from the claims hereinafter set forth.

In the drawings, in which like numerals are used to designate like parts in the several views throughout:

Figure 1 is a side elevational view, with parts broken away, illustrating an automotivel truck having a tiltable dump body mounted thereon and including an hydraulic hoisting mechanism constructed in accordance with the present in- 50 `volition;

Fig. 2 is an enlarged cross-sectional view taken substantially along the line 2-2 of Fig. l:

Fig. 3 is a cross-sectional view taken substantially along the line 3-3 of Fig. 2;

55. Fig. 4 is an end elevational and cross-section (Cl. 3h52) view taken substantially along the line -I of Fig. 2:

FIS. 5 is a view similar to Fig. 2. illustrating another iorm of the present invention; and

Fig. 6 is a cross-sectional view taken substan- 5 tially along the line 8 6 oi Fig. 5.

Referring to the drawings, and referring par.- ticularly to Figs. l through 4 thereof, one embodiment of the present invention is illustrated lo in which a conventional dump truck is shown at i8, having a chassis i2 andla body I4 tiltably mounted thereon for pivotal movement about transversely aligned pivots i8. The chassis i2 is provided with longitudinally extending sill mem- 15 bers Il; and the body H is provided with longitudinally extending body members i9, which are adapted to rest upon-the upper portions of sills i8 when the body is in its lowermost position.

In order to raise and lower the body I 4 about 20 the pivot IB, an hydraulic hoisting device-generally indicated at 2li. is provided. Such hoisting device 20 comprises a cylinder 22 having one end thereof closed by an end plate 24 and the opposite end thereof closed by an end cap 26. 25

vThe cylinder 22 includes a ring-shaped member 23, of greater thickness than the thickness of the major portion of the cylinder 22 secured 4to one end thereof. Such member 23 is formed with an annular internal shoulder 25 and telescopically 30 receives therein the rear end of the cylinder. The 'end cap 26 is removably xed to the member 22 by means of suitable bolts. 'Ihe member 23 is also provided with a tapped and tapered opening which receives a threaded plug 29 for 35 closing the same. The cylinder may thus be illled with the 'actuating fluid through such opening. or such opening may be used to drain the fluid from the cylinder.

.li-piston 28 is slidably mounted for reciproca- .m tion within the cylinder and has a piston rod 30 eoaxially ilxed thereto which projects through a coaxial opening in the end cap 28. A packing means 22 may be suitably mounted on the vend cap in embracing relationship to the piston rod il so as to prevent leakage through the cap opening as the piston rod reciprocates with respect thereto.

The rear end of the piston rod 30 projects beyond the cap 2C and is of reduced diameter. as 5o indicated at 3l. The portion Il is adapted to be removably ilxed to an'angle plate having a top surface portion 3l and a downwardly extending portion 2l at an anglev thereto. The reduced portion 24 may extend through a suitable aper- 55 .2 Y t t turai .the portion as so that it nos against the underside of portion 36 and projects therealong andso that the adjacent enlarged portion abuts against the forward surface of portion 38. A

U-shaped member 40 is disposed under portion 36 walls thereof spaced from each other to provide a chambertherebetween'. The members 46 are generally-triangular in shape, asbest showny in Fig. 2, and the inner edges 48 thereof are adapted to abut against and extend longitudinally ofA the cylinder 22 at diametrlcally opposed points.l The members 46 are so positioned that the apices are disposed adjacent the rear ends of the cylinder with the base ends thereof disposed adjacent the base of the cylinder. The abutting edges of the members 46 are then Welded to the cylinder 22, as indicated at 50; The forward or baseends of the members 46 are closed by end plates which are complementary in shape to the shape of the open ends of the members 46, so that such members, together with the end plates, form enclosed chambers. y

'I'he chambers formed within the wing members 46 form fluid reservoirs, which communicate with the interior ofcylinder 22 through openings 52,

. In order to plvotally mount the hoisting means formed in the cylinder Wall adjacent the cap end of the cylinder.

20 with respect to the chassis, stub pivot shafts 54 are adapted tolproject through openings inthe outside corners of wing members 46 adjacent the base end vof' the cylinder. The stub shafts 54 may be welded'to the members 46 so that thev reservoir chambers are sealed and so .as to -provide .a secure mounting. The ends of the stub shafts 54 are adapted to be received within bearings 66, which are fixed to thesills I8 of the chassis at transversely aligned points.

In order that the hoisting mechanism of the present invention may be applied to any of the various makes of trucks, a pump mounting means is provided on each of the Wings, so that the pump may be mounted on that wing located at the same side as the side of the engine take-off onv the truck. A reinforcing plate member 58 is fixed to the under side of each of the Wings 46 adjacent the base end thereofyand a reinforcingl bracket plate 60 is also fixed `to the top of each of the.

wings 46 in overlying relation to the members 58.

A gear pump 62 of conventional construction is illustrated as bei g mounted on vone of the sides. and` such mounting is effectedby a plurality of bolts 64, which pass through plate member 6|),v

the top and bottom walls of members 46. bracing plate 68, andare threaded in tapped openings .f -1 in thet'o'ppf pump 62v for mounting the pump 62 to theVunder side of wings l46. Spacers in the forni of tubular sleeves 66 embrace the bolts 64,: soV as. to brace the same and limit the tightness with which the pump 6211s drawn against-the under side of the wings 46 to which it is attached.

The Wings 46 are adapted to communicate with necting means.

thev pump 62 through an opening 68 formedP through the bottom'wall of member 46 and through an aligned opening in reinforcing plates 58 a r.Ihe reservoir chamber provided' by that wing 46 on the side of the cylinder to which the pump is not attached has the communicating passage 68 closed by means of a closure plate 10, which is lxed to the bolts 64 by means of nuts l2.

For filling or draining the reservoir chambers povided by wings 46, tapped and tapered openings 14 are provided through 'the top plate 68, and aligned openings in the upperv wall of wings 46. Such openings are closed by a threaded plug 16.

The gear pump 62 is adapted to be driven bf tings 88, which are xed to the end plate 24 and communicate through an opening in the end plate.

It will thus be seen that the reciprocation of the piston 28 is effected by the circulation of the hydraulic fluid within cylinder 22 and that wing 46 to which the pump is attached. The other wing merely forms a storage reservoir and the uid does not circulate therethrough during the operation of the mechanism. Actuation of the pump forces fluid -under pressure through theconduit 86 against the forward sideof" piston 28, thus causing the piston to move toward the cap end. 'I'he fluid within the cylinder 22 is thereby caused to move through one of the openings 62 into the adjacent reservoir and passes therefrom through passage 68 back into the pump. By re- 'versal of the valve lever 84,-the body may be lowered, andthe fluid would flow in the opposite direction.

The piston rod may be connected to the dump body I4' either directly or through suitable con- In the embodiment illustrated, the' piston is shown as being connected tothe dump body through a linkage mechanism. Suitable pivot rods 92 are welded to the inside corner of plate member 36, as shown in Fig. 3, and such pivot shafts extend slightly beyond the endsof plate member 36. l

Similar linkage members areprovided atvthe outside ends of each of the pivot shafts 82 for connection'to the body. Each of such linkage mechanisms includes a lever member 94' plvotally connected to the chassis at 96, and plvotally connected to the projecting endi of pivot shaft 92 -intermediate the ends thereof. Other linkage members 98 have the lower ends thereof plvotally connected to the lower end of levjer 94 at 99, and

have the u pper ends thereof plvotally connected 1 to the longitudinal body members I9, as indicated at llll. The linkage connection just mentioned forms no part of the present invention per se, but is merely illustrative of one manner in which the hydraulic hoisting means may be connected to the body.

From the above description, it will be evident that as the body is being raised or lowered, there 15 means of a flexible ydrive shaft 18, which is cont is considerable stress placed upon the pivotal connections 54. The wing members 48 not only provide a simplified and inexpensive construction for forming reservoirs, but they also serve to stiften and strengthen the construction, so that the load on the pivots 54 is more properly distributed, than in prior constructions.

Referring to Figs. 5 and 6, another embodiment of the present invention is illustrated in which the side wings forming the reservoirs and rein-rfforcing members are of a dierent construction. In this embodiment of the invention, side wings |04, which correspond to the side wings k46 of the embodiment above described, are provided. Eachof such side wings |04 is formed of upper and lower, complementary sheet metal stampings |06 and |08, which are resistance butt welded together. In plan, the side wings |04 are generally triangular in shape and have a base end I0, which is welded to the base end of the cylin- 1 der 22. Communicating conduit portions ||2 converge toward the cap end of the cylinder 22 and the ends thereof are Welded to the cylinder 22 adjacent the cap end in overlying relation to the communicating openings 52. The pivot shafts 54 are welded t0 the Wings |04 at transversely aligned points for pivotal connection to the chassis. Pump mounting means similar to those described above are also provided on the base ends of each of the side wings |04, as indicated at 60 and 64. The operation of this structure is the same as that described above, and the forces on the pivot 54 are distributed thereto in the same manner.

It will be appreciated that in both of the embodiments above described the side wings have dual functions. 'Ihe wings act as fluid reservoirs and also provide a simplied construction in prior constructions employing the ordinary crossmember abutting the end of the cylinder.

Formal changes may be made in the speelseV embodiment of the invention described without departing from the spirit and substance of the invention, the scope of which is commensurate with the appended claims.

What is claimed is: Y

1. In a truck body hoisting mechanism, an hydraulic cylinder having a base end and a cap end, a piston and piston rod reciprocably mounted therein with said `rod extending through said cap end, side members generally triangular in shape extending longitudinally of said cylinder and iixed to the outside thereof forming reservoir chambers, the bases of said side members being disposed adjacent the bas'e end of said cylinder with the apex of said side members disposed adjacent said cap end, means communicating said' chambers with lthe interior of said cylinder, and aligned pivotal mounting means connected to said side members adjacent the base end of said cylinder.

2. In -a ltruck body hoisting mechanism, anv

the bases thereof adjacent the base of said cylinl der, means communicating said chambers with the interior of said cylinder, pivotal mounting means ixed to said side members adjacent the bases thereof, and pump mounting means fixed to said side members on both sides of said cylinder.

3. In a truck body hoisting mechanism, an

hydraulic cylinder having a base end and a cap end, a piston and piston rod reciprocably mounted therein with the rod extending through said cap end, side members disposed at diametrically opposed positions wlth respect to said cylinder and der, means communicating said chambers with the interior of said cylinder, and aligned pivotal mounting means fixed to said side members adjacent the base end of said cylinder.

4. In a truck body hoisting mechanism, an hydraulic cylinder'havlng a base end and a cap end, a piston and piston rod reciprocably mounted therein with said piston rod extending through said cylinder, side members extending longitudinally of said cylinder at diametrically opposed portions thereof and nxed to the outside thereof, forming reservoir chambers, means communicating said chambers with the interior pf said cylinder, each of said side members comprising a pair of complementary stamped sections welded together and being 'generally triangular in shape, said side members being welded to said cylinder adjacent the base end thereof and adjacent the cap end thereof, and pivotal mounting means iixedly connected to said side members.

EDWARD R. BARRETT. 

